BEIJING — China's ruling Communist Party announced an investigation into a feared ex-security chief on Tuesday, demonstrating President Xi Jinping's firm grip on power and breaking a long-standing taboo against publicly targeting the country's topmost leaders.
If he goes to trial, Zhou Yongkang would be the highest-level official to be prosecuted since the 1981 treason trial of Mao Zedong's wife and other members of the "Gang of Four," who mercilessly persecuted political opponents during the chaotic 1966-76 Cultural Revolution.
Until his retirement in 2012, the square-jawed, granite-faced Zhou was one of nine leaders in the party's ruling inner circle — the Politburo Standing Committee — whose incumbent and retired members had been considered off-limits for prosecution in an unwritten rule aimed at preserving party unity.
However, Xi, who is party leader as well as president, has vowed to go after both low- and high-level officials in his campaign to purge the party of corruption and other wrongdoing that have undermined its legitimacy in the public eye.
The party's antigraft watchdog, the Central Commission for Discipline Inspection, said on its website Tuesday that it is investigating Zhou, 71, for serious violations of party discipline. Although it gave no details, such an announcement typically paves the way for the official to be ousted from the party and face prosecution.
It also ended months of speculation over Zhou's fate amid reports of his family's amassing great wealth and as authorities began investigating dozens of his associates including several high-ranking officials and businesspeople. One after another, the associates disappeared into the custody of party investigators, foreshadowing problems ahead for Zhou.
On Tuesday, the Chinese news magazine Caijing reported that Zhou's son was arrested by prosecutors in the city of Yichang in Hubei province, accused of "illegal business operations."
By targeting Zhou, who had commanded China's massive domestic security apparatus before his retirement and was once perceived as untouchable, Xi shows the considerable power he has amassed since he took the helm of the party in 2012.